Tamping device for a curb and gutter paving machine



Oct. 25, 1960 A. B. SUPJECT 2,957,397

TAMPING DEVICE FOR A CURB AND GUTTER PAVING MACHINE Filed Dec. 19, 1957 2 Sheets-Sheet 1 I[[ M II INVENTQR. fi/v r/m/v Y i. Jun/E T 6 a 6 3 BY arramrzr:

Oct. 25, 1960 A. B. SUPJECT 2,957,397

TAMPING DEVICE FOR A CURB AND GUTTER PAVING MACHINE Filed Dec. 19, 1957 2 Sheets-Sheet 2 INVENTOR. /-7/v THO/V) 6. 50min- TAMPING DEVICE FOR A CURB AND GUTTER PAVING MACHINE Anthony B. Supject, 2118 Humphrey, Kalamazoo, Mich.

Filed Dec. 19, 1957, Ser. No. 703,888

3 Claims. (Cl. 9446) This invention relates in general to a tamping mechanism for a curb and gutter paving machine and, more particularly, to a type of tamping mechanism which is readily adjustable for tamping various sizes and shapes of curb being formed by the machine with which it is associated.

The construction and operation of machines for automatically forming strips of paved concrete are Well known. Also, the advantages of tamping concrete as it is being laid are also known. For example, it has been found that cavities, air pockets and similar defects will develop in the concrete, particularly below a curbing strip, unless such concrete is thoroughly tarnped while it is being laid. These defects, if not eliminated, not only weaken the curb structure at unpredictable points, but also cause cave-ins or sags to occur in the curbing before it can set.

However, while such tamping mechanism has been utilized previously, it has normally been located in a fixed position with respect to the remainder of the machine. This is satisfactory where the machine is to be used with curb and gutter constructions of fixed dimensional relationships, but where a single machine is to be used with curb and gutter constructions of different heights and widths, then the tamping mechanism should be adjustable relative to the rest of the machine. Such a device, insofar as I am aware, has not previously been provided.

Accordingly, a primary object of this invention is the provision of an improved tamping mechanism mountable upon an automatic machine for laying a strip of concrete or the like in the form of a curb or a gutter.

A further object of this invention is the provision of a tamping mechanism, as aforesaid, which is driven by the propelling mechanism of the paving machine and which includes one or more tamping arms which are adjustable, both vertically and in a direction crosswise of the direction of movement of the tamping machine upon which they are mounted.

A further object of this invention is the provision of a tamping mechanism, as aforesaid, which is fool-proof in operation, which requires little or no maintenance, which is easy to adjust and which can be adapted for use with existing paving machines of the type particularly designed for laying curbs and gutters.

Other objects and purposes of this invention will become apparent to persons familiar with this type of equipment upon reading the following specification and examining the accompanying drawings, in which:

Figure 1 is a broken, side-elevational view of a paving machine embodying a tamping mechanism characterizing the invention.

Figure 2 is a broken fragment of Figure 1 indicated by the cutting line IIII in Figure 1.

Figure 3 is a broken, sectional view substantially as taken along the line III-III of Figure 1.

Figure 4 is a broken fragment of Figure 3 showing parts thereof in a different operating position.

Figure 5 is a sectional view taken .along the line V--V of Figure 3.

Figure 6 is an enlarged fragment of Figure 3 indicated by the cut-ting line VI-VI in Figure 5.

For the purpose of convenience in description, the terms upper, lower and derivatives thereof, as used herein, will have reference to the corresponding locations of parts in the machine to which this invention relates when in their normal positions of operation, which are shown in Figures 1, 3 and 4. The terms inner, outer and derivatives thereof will have reference to the geometric center of said tamping mechanism and parts associated therewith. The terms forward, rearward and derivatives thereof will have reference to the normal direction of movement of the paving machine.

General description In order to meet the objects and purposes of this invention, including those set forth above, a curb and gutter paving machine has been provided with a tamping mechanism comprised of a substantially horizontal crankshaft, rotatably supported upon the forward end of the paving machine so that its rotational axis is substantially parallel with the direction of movement of said machine. Said crankshaft is connected to, and driven by, the drive unit, which is also utilized to propel the machine. The crankshaft is supported upon a frame structure which slidably supports one or more vertically reciprocable members supported upon said crankshaft for reciprocation thereby. One or more tamping arms are adjustably mounted respectively upon each said reciprocable member and extendable downwardly toward and to the upper surface of the concrete or other material which is poured for the purpose of forming a curb.

Detailed construction As shown in Figure 1, the tamping mechanism 10 includes a frame structure 11 which is supported upon the carriage 12 of a curb and gutter paving machine 13. The carriage 12 is in turn supported by wheels indicated at 15 and 16 upon rails 17 and 18 (Figure 3), which also provide the forms between which the concrete strip 19 is laid. The wheels 15 and 16 are driven by means, such as an internal combustion engine 21, operating through a clutch 22, a gear box 23, and other connecting mechanism indicated generally at 24. The paving machine 13 has a hopper 26 (Figures 1 and 3) which is disposed directly below the frame structure 11 of said tamping mechanism 10 and directly over the curb portion 27 of the concrete strip 19. A screed or trowel 28 (Figures 1 and 3) is supported upon and beneath the carriage 12 between the rails 17 and 18.

For further details with respect to the general structure of the paving machine 13, reference is made to Patent No. 2,623,446, issued to Clark and Andrus.

The frame structure 11 (Figures 1 and 2) of the tamping mechanism It has a rearward end wall 31 which is mounted upon, and extends upwardly from, the carriage 12 near the forward end thereof. Means, such as the brace member 32, may be provided for securing said end wall 31 with respect to said carriage. Said frame structure 11 also has a pair of preferably parallel sidewalls 33 and 34 which are secured to and extend forwardly from, the end wall 31, said sidewalls being spaced upwardly from the hopper 26. A forward end wall 36 extends between, and is secured to the forward ends of, the side walls 33 and 34. A horizontal camshaft 37 extends through, and is rotatably supported upon, the end walls 31 and 36 by means, such as the bearings 38 and 39, respectively. A coverplate 41 is removably supported upon the upper edges of the end and side walls of said frame structure 11. A driven sprocket 42 is mounted upon, and rotatable with, the rearward end of the camshaft 37. A drive sprocket 43 is supported upon, and rotatable with, an output shaft 44 of the gearbox 23. The driven sprocket Patented Oct. 25, 1960 is connected to the drive sprocket by any convenient means, such as a chain 46.

As shown in Figures 2 and 3, a pair of tamper support members 47 and 48 are slidably mounted upon, and between, the side walls 33 and 34. Inasmuch as the support members 47 and 48 may be, and preferably are, substantially identical, the support member 47 will be described in detail and such description will be understood to apply to the support member 48. Accordingly, parts of the support member 48 will be indicated by the same numerals, plus the sufiix a, as their counterparts in the support member 47.

The support member 47 (Figures 2, 3 and 6) is comprised of a pair of parallel and vertical elements 50 and 51, between which the vertically spaced, co-planar plates 52 and 53 are secured, in any convenient manner, such as by welding. A pair of cam engaging bars 55 and 56 are secured to, and extend along, the adjacent parallel edges of the upper and lower plates 52 and 53, respectively. Accordingly, the cam bars 55 and 56 and the portions of the vertical elements 50 and 51 extending between said cam bars combine to define a rectangular cam opening 57.

The vertical element 50 is slidably disposed between the vertical guide rails 58 and 59 mounted upon the inner surface of the side wall 33 near the forward end thereof. The vertical element 51 is slidably disposed between a pair of guide rails 61 and 62 mounted upon the inner surface of the side wall 34 so that said support member 47 is substantially parallel with the end wall 36.

The camshaft 37 extends through the cam opening 57 in the support member 47 and supports a pair of axially spaced, circular cams. The cams 63 and 64 are eccentrically secured to, and rotatable with, the camshaft 37 by means of keys 66. Said earns 63 and 64 are arranged so that their throws are in radially opposite directions with respect to the cam shaft 37, as shown in Figures 3 and 4. The cam 63 (Figures 2 and 4) is snugly, but slidably, disposed between the cam bars 55 and 56 within the cam opening 57. The support member 48 (Figures 2 and is mounted upon, and within, the frame structure 11, rearwardly of the support member 47, by means of the guide rails 58a, 59a, 61a, and 62a. The support member 48 is preferably parallel with the support member 47 and spaced therefrom a distance substantially equal to the distance between the cams 63 and 64. Thus, the cam 64 is disposed within the cam opening 57a between the cam bars 55a and 56a.

The lower end of the lower plate 53 of said support member 47 has a pair of vertically spaced, horizontally elongated slots 67 and 68 (Figures 3 and 4) which are preferably parallel. A tamping arm 69, having a lengthwise slot 71 in its upper end is removably supported upon the lower plate 53 by means of a pair of bolts 72 and 73 (Figure 5), which extend through the slots 67 and 68, respectively, and through the slot 71, where they are engaged by nuts 77 and 78. Thus, the tamping arm 69 is adjustable, both vertically and crosswise, of the lower plate 53, hence of the support member 47. Said tamping arm 69 has a tamping shoe 74 secured to its lower end and, in this particular embodiment, sloped with respect to the lengthwise extent of said tamping arm 69. Accordingly, and as shown in Figure 3, the tamping arm 69 may be supported upon the support member 47 so that the tamping shoe 74 will tend to drive the concrete 19 toward the lower outside corner 76 of said curb portion 27.

The tamper support member 48 is arranged to support a tamping arm 69a, having a tamping shoe 74a, on the lower end of the lower plate 53a in the same manner as set forth above with respect to the tamping arm 69 and support member 47.

Operation Prior to operation of the tamping mechanism 10, the

tamping arms 69 and 69a are adjusted upon the tamper support members 47 and 48, respectively, so that they will engage the concrete in the curb portion 27 (Fig ure 3), at the proper level and at the proper position crosswise of the curb portion 27. This is accomplished, for example, by loosening the nuts 77 and 78 on the bolts 72 and 73, after which the slots 67, 68 and 71 permit rather extensive vertical and horizontal adjustment of the tamping arm 69, with respect to the support member 47. After the proper position of the tamping arm 69 is established, the nuts 77 and 78 are tightened upon the bolts 72 and 73. As shown in Figure 4, the tamping arm 69a may be adjusted upon the tamper support member 48 in a similar manner.

The tamping arms 69 and 69a are preferably arranged upon their respective support members 47 and 48 so that they are relatively close to the inner wall of the hopper 26, hence the inner wall of the curb portion 27. Accordingly, the vertical reciprocation of the tamping shoes 74 and 74a which is produced by the cams 63 and 64, will tend to ram the concrete back into the lower outside corner 76 of the curb portion 27. Furthermore, this improved tamping action will not only remove the air pockets from the freshly poured concrete, but will also tend to move the larger solids in the aggregate toward the bottom, where they will not interfere with the screed 28 and thereby produce defects in the surface of the concrete.

Due to the opposite throw of the earns 63 and 64, the one tamping arm 69, for example, will be moving upwardly when the other tamping arm 69a is moving downwardly. More specifically, the tamper support member 47 (Figure 6) for example, will move from its solid line position 47 to its broken line position 47b and then back to its solid line position 47 during a single rotation of the cam shaft 37, hence of the cam 63 supported thereon.

Where the curb portion 27 is relatively narrow, the tamping arms 69 and 69a may be substantially aligned lengthwise of the machine, as shown in Figure 3.

Where the curb portion is fairly wide, as indicated at 27a in Figure 4, the tamping arms 69 and 69a may be advantageously staggered crosswise of the concrete strip 19. Other arrangements are also possible and will be obvious in view of the foregoing. Further, the tamping arms 69 and 69a may be adjusted vertically to fit curbs of different heights. Accordingly, it will be seen that a variety of both vertical and transverse adjustments, as desired, can be made in the positions of the tamping arms 69 and 69a with respect to their support members 47 and 48.

Although a particular preferred embodiment of the the invention has been disclosed hereinabove for illustrative purposes, it will be understood that variations of such disclosure, which lie within the scope of the appended claims, are fully contemplated.

I claim:

1. In a curb and gutter paving machine having a wheeled carriage supporting a driving unit and means for forming a curb, the combination comprising: a frame structure mounted upon said carriage and disposed above said curb forming means; a camshaft supported upon said frame structure for rotation about a substantially horizontal axis in longitudinal alignment with the paving machine and means drivingly connecting said driving unit to said camshaft; a pair of vertically reciprocable support members slidably supported in said frame structure and spaced axially along said camshaft from each other; a pair of cams eccentrically supported upon, and rotatable with, said camshaft, the throws of said cams being in diametrically opposite directions, a pair of horizontal, vertically spaced bars on each of said support members, one of said cams being disposed between and engaged by each pair of bars for effecting said vertical reciprocation of said members so that when one of said support memhers is in its lower position, the other is in its upper position and vice versa; and a pair of tamping arms supported upon said support members and extendable downwardly into the zone defined by said curb forming means; and means including a horizontal slot in each support member and a vertical slot in each arm with a pin extending therethrough for adjusting said arms vertically and transversely of said machine.

2. The structure of claim 1 wherein said support members have horizontally elongated openings in which said bars are rigidly disposed along the upper and lower edges thereof, said cams being vertically snugly and horizontally slidably received between said bars and into said elongated openings.

3. In a curb and gutter paving machine having a wheeled carriage supporting a driving unit and a hopper supported on the carriage for supplying material to a curb and gutter form, the combination comprising: a substantially rectangular frame structure mounted upon said carriage above said hopper, said frame structure having a pair of side walls extending substantially parallel with the direction of movement of said carriage and a pair of end walls extending substantially transverse thereto; a camshaft rotatably supported on and extending between said end walls for rotation about a substantially horizontal axis and means drivingly connecting said driving unit to said camshaft for rotating same; a pair of axially spaced cams eccentrically secured to said camshaft for rotation therewith, the throws of said cams being diametrically oppositely disposed; a pair of axially spaced, tamper support frames within said frame structure and extending between the side walls thereof, said tamper support frames each having a pair of vertical flanges vertically slidably disposed adjacent the respective side walls of said frame structure; guide rails on said side walls for slidably guiding vertical movement of said vertical elements; each of said tamper support frames including a pair of vertically aligned, and vertically spaced plates extending between and secured to said vertical flanges, the adjacent edges of each pair of said plates having a pair of cam-engaging bars secured thereto, said camshaft extending through said tamper support frames between the adjacent edges of said plates and said cams on said camshaft bearing against said cam bars on said tamper support frames, respectively; the lower plate on each of said tamper support frames having a pair of vertically spaced, horizontally extending slots therethrough adjacent the lower end thereof; a pair of vertically extending tamper bars having tamping shoes at the lower end thereof, said tamper bars each having a vertically extending slot through the upper portion thereof; each of said tamper bars being disposed against a surface of the lower plate of one of said tamper support frames so that the vertical slot therein crosses both of the horizontally extending slots in said lower plate; and bolts extending through the points at which said slots cross for releasably securing said tamper bars in fixed, but horizontally and vertically adjustable, position on said lower plates.

References Cited in the file of this patent UNITED STATES PATENTS 1,887,341 Venable Nov. 8, 1932 2,215,455 Abernathy et a1 Sept. 24, 1940 2,295,322 Arborio et al. Sept. 8, 1942 2,380,435 Heltzel July 31, 1945 2,623,446 Clark et a1. Dec. 30, 1952 

